Yes @Bunniekins it definitely is. I knew there was a strong chance of my insomnia coming back once I was off my meds. That's why I made sure I worked on sleep hygiene with my psychologist a couple of months before stopping the meds. The medication I was on was for my mental health and my sleep. 
My insomnia started when I was 15. I was hospitalised for 6 months with anorexia nervosa. The insomnia started when I was at my worst. When my body was shutting down. It was my bodies way of trying to keep me alive. But even as I recovered and ate well it never went away, it stuck around. It's like my brain never switched off from 'if you sleep you die' mode. The psychiatrist explained it to me as my body was worried if I went to sleep I wouldn't wake back up again. And that my body used less energy laying still in a hospital bed staring at the ceiling rather than dreaming. That's what started it, we just don't know why It's continuing. We think maybe something biological happened when I was really sick with the anorexia